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View Full Version : Inrush current.....AGAIN!!


Tim R.
11-08-2010, 10:15 PM
Well, I was worried about it when I placed the transformer and sure enough. My GFI keeps popping. I have a dedicated outlet that has about 6' of wire between it and the panel. My lights fire up fine and cycle fine when I am there testing but sometime in the night the GFI kicks off. Only 6.5 amps on the primary. Transformer is a 1200 watt unit with a photocell. It has 4-300 watt circuits. I am reading between 17 to 20.5 amps on the secondary circuits. What have you guys had success with to overcome problems such as this or am I barking up the wrong tree? Thanks in advance for your input.

Gr1ffin
11-09-2010, 03:01 AM
Tim,

You are more skilled and experienced than I am however you might try these if you didn't already check, as I have encountered the below which caused a gfi to trip intermittently (every couple of days). If its intermittently and it is not the load issue I might check:
-to see if there is an association between the irrigation/rainfall and it tripping. If the GFI is not in a weatherproof box/gets wet from a sprinkler system, I have seen it trip gfi's.
-exposed wire, splice, short that may be subtle but can cause a trip either over time or from the above (water).

Sincerely,

Alan

Readjusting to the 12 hr time zone diff is killing me!

cheapcuts1
11-09-2010, 06:06 AM
BAD GFI, or moisture as said above. ! Try placing a in use bubble cover over the new gfi .

Tim R.
11-09-2010, 06:36 AM
Its a new GFCI in an in-use "bubble cover"
There hasn't been any rain or irrigation so that is not the issue either. I had this same problem on a couple 1800 watt units that were placed next to panels. I took the photocells off and moved the control to an analog timer and they seemed to hold fine but I can't really go that route here. I think I will slap on a digital Astro timer and see if my luck improves. I checked all my individual runs looking for a spiked load due to an exposed wire but all the secondary amp loads per run checked out fine which leads me back to thinking it has something to do with the panel. Maybe adding full surge protection to the panel??? I am just wondering if they are getting some dirty power during the evening when the power company shifts demand.

RLI Electric
11-09-2010, 07:48 AM
I like to put a whole house surge protector on all my larger jobs. A field of copper in the yard can invite trouble, ask any invisible dog fence owner. GFCI outlets are cheap, try a different one. They are much better than they used to be but if I had a nickel for every bad one out of the box, I would have, well, maybe 20 bucks. How about a faceless gfci or a gfci breaker with a surge protected outlet. We use these for home theater installs. Protect the outlet behind the wall mounted tv. You might be able to use the same setup here. Reality, it's probably the $7.00 gfci receptacle.

Pro-Scapes
11-09-2010, 08:08 AM
Tim this was a common problem I had especially when mounting so close to a panel on early installs. They are all working fine now by installing surge suppressors inline (mdl made a wall hanging one that plugged into transformers) but it really made installations look dirty.

Can the trans be hardwired ?

I used to use 1200w transformers all the time. Some have been fine and others troublesome. My solution was easy.

I started to use multiple smaller transformers vs 1 larger one. This made wiring easier... things more reliable. No problems yet.

I also got in the habit of hard wiring transformers. This looks cleaner (and I know you do some really clean installs) Less problems with things getting wet... people wont tamper with things...No one will be plugging power tools or other loads into your outlets (I don't care if its dedicated. Someone will plug something into it at some point and wont care if its tripped or not)

Sorry for the blurry picture. It came off my phone. The loose wire you see behind the power mast is not mine. The flex has also been strapped since the pic. The T103 timer you see was used at the clients request for simplicity and he was familiar with these timers. This timer also feed 2 additional Unique Direct burial transformers located on the opposite side of the house via a wire placed in the crawlspace. Ultra reliable and everything comes on at once.

The 2 LB conduit bodies you see at the bottom of the low voltage wiring pass thru this wall into the front yard. I kept them low enough you cannot see the 2 LB's on the other side of the wall once we put the pinestraw back. NOTHING is visable unless your in this utility cubby

RLDesign
11-09-2010, 08:31 AM
Its a new GFCI in an in-use "bubble cover"
There hasn't been any rain or irrigation so that is not the issue either. I had this same problem on a couple 1800 watt units that were placed next to panels. I took the photocells off and moved the control to an analog timer and they seemed to hold fine but I can't really go that route here. I think I will slap on a digital Astro timer and see if my luck improves. I checked all my individual runs looking for a spiked load due to an exposed wire but all the secondary amp loads per run checked out fine which leads me back to thinking it has something to do with the panel. Maybe adding full surge protection to the panel??? I am just wondering if they are getting some dirty power during the evening when the power company shifts demand.

Hello Tim,

Maybe try a GFI breaker in the panel. They tend to be a little better (about $60) with situations like this. We spec them in any situation that is applicable, especially if we have 3 transformers relayed or UPB devices activated at the same time on the same circuit.

I hope this helps.

Talk soon.

Tanek
Reynolds Lighting

Pro-Scapes
11-09-2010, 09:01 AM
It should also be noted... not all bubble covers are created equal. I have found the Red Dot ones to work well in my when I am forced to use a GFCI. I also have my EC fix any noticable violations outside the home and he often gets extra work from the homeowners who need a little updating elsewhere.

Still no substitue for hardwiring!

Tim R.
11-09-2010, 09:12 AM
Billy, where do you get your in-line surge suppressors? Thanks for all the input guys.

Pro-Scapes
11-09-2010, 10:50 AM
I think it was kichler years ago when MDL had the problem with inrush. 1200w transformers just draw too much at initial start up to be on GFCI and can also trip breakers quick.

With it being that close is a 30a breaker and 10ga wire an option ?

20/20 breakers and 2 circuits hardwired with 2 600w boxes is where i would go.

The Gambino Transformers I use feature an inrush protection device. As you can tell by the picture generation 2 has been completly redesigned to be even more robust.

RLDesign
11-09-2010, 11:14 AM
Tim this was a common problem I had especially when mounting so close to a panel on early installs. They are all working fine now by installing surge suppressors inline (mdl made a wall hanging one that plugged into transformers) but it really made installations look dirty.

Can the trans be hardwired ?

I used to use 1200w transformers all the time. Some have been fine and others troublesome. My solution was easy.

I started to use multiple smaller transformers vs 1 larger one. This made wiring easier... things more reliable. No problems yet.

I also got in the habit of hard wiring transformers. This looks cleaner (and I know you do some really clean installs) Less problems with things getting wet... people wont tamper with things...No one will be plugging power tools or other loads into your outlets (I don't care if its dedicated. Someone will plug something into it at some point and wont care if its tripped or not)

Sorry for the blurry picture. It came off my phone. The loose wire you see behind the power mast is not mine. The flex has also been strapped since the pic. The T103 timer you see was used at the clients request for simplicity and he was familiar with these timers. This timer also feed 2 additional Unique Direct burial transformers located on the opposite side of the house via a wire placed in the crawlspace. Ultra reliable and everything comes on at once.

The 2 LB conduit bodies you see at the bottom of the low voltage wiring pass thru this wall into the front yard. I kept them low enough you cannot see the 2 LB's on the other side of the wall once we put the pinestraw back. NOTHING is visable unless your in this utility cubby

Hello All,

In NJ, we cannot hardwire transformers. The inspector requires the outlet to be GFI protected, permitted, inspected and installed by a licensed electrician. We also must use a transformer that is rate for the application and installed to code. We cannot install inside structures and run outwards, but we can install outside and run Qtran inside the home outside accent lights. The attached pic is how we install our transformers. Either UPB devices or relays are located inside, powdercoated to match outside of home, etc. We try to always use the deep bubble cover. We try to either breaker GFI or use the weatherproof GFI receptacles. I always include an upgrade to the GFI outlet in my proposals to eliminate problems.

I hope this helps fix your problems. I never use transformers over 1000 watts, which draw about 16 amps as they power up (that is why I design with the 20 amp GFI protected circuit). A local electrician just informed me that direct burial transformers are allowed to be hardwired in NJ, but they must be piped to fixtures and switched.

Best regards,

Tanek Reynolds Lighting

Talk soon. Tanek Hood Reynolds Lighting

RLI Electric
11-09-2010, 03:58 PM
Pro Scapes, if I am reading the question right then no, you cannot throw a 15 or a 20 amp device on a 30 amp breaker

David Gretzmier
11-10-2010, 09:36 PM
1st, replace the GFCI outlet. make sure it is a good HD 20 amp one. In Christmas lights, we replace probably 15-20 of those per year. once a GFCI has been reset a dozen or so times, it is no longer whatever it was rated at from the get go. the springs on new ones are just better. Even ones that are a year old can pop. I have seen a 1200 watt trans pull a 16 plus amp load and trip a 20 amp breaker.

normally a gfci pop has to do with shorts and moisture. sometimes a spark can happen where it is plugged in, and I have had some luck pushing the prongs together on the plug for the trans.

hardwiring the trans inside the outlet box and getting rid of the outlet is an option, and a 20 amp gfci breaker tends to be more robust than an outlet.